Display panel, manufacturing method thereof and display apparatus

ABSTRACT

Provided is a display panel, including: a base substrate, a light emitting device layer provided on the base substrate and including light emitting devices, and a light adjustment structure layer provided at a side of the light emitting device layer facing away from the base substrate and including light adjustment units and a dielectric layer covering the light adjustment units. Each light adjustment unit has a smaller refractive index than the dielectric layer and includes a light adjustment sub-section and a through hole penetrating the light adjustment unit in a direction perpendicular to the base substrate. The through hole overlaps one light emitting device, and the light adjustment sub-section surrounds the through hole. For one light adjustment unit, a thickness of the light adjustment sub-section gradually increases in a direction from the through hole to the light adjustment sub-section.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 16/912,552, filed on Jun. 25, 2020, which claims priority to ChinesePatent Application No. 202010374758.7, filed on May 6, 2020. All of theaforementioned applications are hereby incorporated by reference intheir entireties.

TECHNICAL FIELD

The present disclosure relates to the field of display technology, forexample, to a display panel, a manufacturing method thereof and adisplay apparatus.

BACKGROUND

Currently mainstream display apparatuses include a liquid crystaldisplay apparatus and an organic light emitting display apparatus. Inthe liquid crystal display apparatus, since liquid crystals do not emitlight, it is needed to provide a backlight module that provides a lightsource for the liquid crystal display panel, so that the displayapparatus has a relatively large overall thickness and a relativelylarge weight. In the organic light emitting display apparatus, anorganic light emitting diode (OLED) is used as a light emitting device,which has characteristics of self-illumination and requires for noadditional light source, which facilitates overall thinning andlightness of the display apparatus, thereby achieving manufacturing of aflexible display screen. In addition, the organic self-illuminationdisplay technology also has characteristics such as a fast responsespeed and a wide viewing angle. Therefore, the organic self-illuminationdisplay technology has become a focus of current research. However, inthe current organic light emitting display technology, part oflarge-angle light emitted by the light emitting device is limited to aninterior of the display panel and cannot exit the display panel tocontribute to light emitting of pixels, which affects an overall lightextraction efficiency of the light emitting device.

SUMMARY

An embodiment of the present disclosure provides a display panel, amanufacturing method thereof, and a display apparatus, to solve atechnical problem of the low light extraction efficiency of the lightemitting device, which would otherwise affect power consumption of thedisplay panel.

In a first aspect, an embodiment of the present disclosure provides adisplay panel, including:

a base substrate;

a light emitting device layer provided on the base substrate andincluding a plurality of light emitting devices; and

a light adjustment structure layer provided at a side of the lightemitting device layer facing away from the base substrate, wherein thelight adjustment structure layer includes a plurality of lightadjustment units and a dielectric layer covering the plurality of lightadjustment units, each of the plurality of light adjustment units has asmaller refractive index than the dielectric layer, each of theplurality of light adjustment units includes a light adjustmentsub-section and a through hole penetrating the light adjustment unit ina direction perpendicular to the base substrate, the through holeoverlaps one of the plurality of light emitting devices, and the lightadjustment sub-section surrounds the through hole.

For one of the plurality of light adjustment units, a thickness of thelight adjustment sub-section gradually increases in a direction from thethrough hole to the light adjustment sub-section.

In a second aspect, an embodiment of the present disclosure furtherprovides a display apparatus, including the display panel according toany embodiment of the present disclosure.

In a third aspect, an embodiment of the present disclosure also providesa manufacturing method of a display panel, and the manufacturing methodincludes:

providing a base substrate;

forming a light emitting device layer on the base substrate, the lightemitting device layer including a plurality of light emitting devices;

forming a light adjustment structure layer at a side of the lightemitting device layer facing away from the base substrate, wherein saidforming light adjustment structure layer includes: forming a pluralityof light adjustment unit precursors by using an inkjet printing process;and evaporating solvent to obtain a plurality of light adjustment units,wherein each of the light adjustment units includes a light adjustmentsub-section and a through hole penetrating the light adjustment unit ina direction perpendicular to the base substrate, the through holeoverlaps one of the plurality of light emitting devices, the lightadjustment sub-section surrounds the through hole, and for one of theplurality of light adjustment units, a thickness of the light adjustmentsub-section gradually increases in a direction from the through hole tothe light adjustment sub-section; and

forming a dielectric layer on the plurality of light adjustment units,wherein each of the plurality of light adjustment units has a smallerrefractive index than the dielectric layer.

BRIEF DESCRIPTION OF DRAWINGS

In order to illustrate technical solutions of embodiments of the presentdisclosure, the accompanying drawings used in the embodiments or theprior art are introduced hereinafter. Obviously, these drawingsillustrate some embodiments of the present disclosure.

FIG. 1 is a cross-sectional schematic diagram of a display panel in therelated art;

FIG. 2 is a schematic top view of a part of a display panel according toa representative embodiment of the present disclosure;

FIG. 3 is a cross-sectional schematic diagram at a position of a tangentline A-A′ in FIG. 2 ;

FIG. 4 is another cross-sectional schematic diagram of a display panelaccording to a representative embodiment of the present disclosure;

FIG. 5 is another cross-sectional schematic diagram of a display panelaccording to a representative embodiment of the present disclosure;

FIG. 6 is another cross-sectional schematic diagram of a display panelaccording to a representative embodiment of the present disclosure;

FIG. 7 is another cross-sectional schematic diagram of a display panelaccording to a representative embodiment of the present disclosure;

FIG. 8 is another cross-sectional schematic diagram of a display panelaccording to a representative embodiment of the present disclosure;

FIG. 9 is a schematic top diagram of a part of a display panel accordingto a representative embodiment of the present disclosure;

FIG. 10 is a cross-sectional schematic diagram at a position of atangent line BB′ in FIG. 9 ;

FIG. 11 is a schematic diagram of a principle of the embodimentcorresponding to FIG. 10 ;

FIG. 12 is another cross-sectional schematic diagram of a display panelaccording to a representative embodiment of the present disclosure;

FIG. 13 is another cross-sectional schematic diagram of a display panelaccording to a representative embodiment of the present disclosure;

FIG. 14 is another simplified cross-sectional diagram of a display panelaccording to a representative embodiment of the present disclosure;

FIG. 15 is another schematic top diagram of a display panel according toa representative embodiment of the present disclosure;

FIG. 16 is another cross-sectional schematic diagram of a display panelaccording to a representative embodiment of the present disclosure;

FIG. 17 is another cross-sectional schematic diagram of a display panelaccording to a representative embodiment of the present disclosure;

FIG. 18 is another cross-sectional schematic diagram of a display panelaccording to a representative embodiment of the present disclosure;

FIG. 19 is a schematic diagram of a principle of the correspondingembodiment of FIG. 18 ;

FIG. 20 is a schematic diagram of a display apparatus according to arepresentative embodiment of the present disclosure;

FIG. 21 is a first flowchart of a manufacturing method of a displaypanel according to a representative embodiment of the presentdisclosure;

FIG. 22 is a second flowchart of a manufacturing method of a displaypanel according to a representative embodiment of the presentdisclosure; and

FIG. 23 is a third flowchart of a manufacturing method of a displaypanel according to a representative embodiment of the presentdisclosure.

DESCRIPTION OF EMBODIMENTS

In order to better understand technical solutions of the presentdisclosure, the embodiments of the present disclosure will be describedin details with reference to the drawings. It should be clear that thedescribed embodiments are representative of the embodiments of thepresent disclosure rather than all of the embodiments.

The terms used in the embodiments of the present disclosure arerepresentative for the purpose of describing specific embodiments,rather than limiting the present disclosure. The singular form “a”,“an”, “the” and “said” used in the embodiments and claims shall beinterpreted as also including the plural form, unless indicatedotherwise in the context.

FIG. 1 illustrates a cross-sectional schematic diagram of a displaypanel in the related art. As shown in FIG. 1 , in the related art, aplurality of film layers is provided on a light emitting device P′, suchas an encapsulation structure layer 11′, an optical adhesive layer 12′,a protective cover 13′, etc. If respective film layers are made ofdifferent materials, then refractive indexes of the respective filmlayers are different. During display, the light emitting device P′ emitslight at a plurality of angles, and both light S1′ and light S2′ asshown in FIG. 1 can exit the display panel, to contribute to the lightemitting of the pixels. However, since light S3′ satisfies conditions oftotal reflection at interfaces of the film layers in the display panel,the light S3′ is restricted inside the display panel after totalreflection, and light S4′ is totally reflected at an interface betweenthe display panel and the air and thus restricted inside the displaypanel. That is, neither the light S3′ nor the light S4′ can exit thedisplay panel, thereby affecting a light extraction efficiency of thelight emitting device.

Based on the above problems, an embodiment of the present disclosureprovides a display panel, a manufacturing method thereof and a displayapparatus. By providing a light adjustment structure layer on the lightemitting device layer, large-angle light emitted from the light emittingdevice can have a light path changed by a light adjustment unit in thelight adjustment structure layer, so as to reduce an angle between alight propagation direction and a direction perpendicular to a basesubstrate, which is equivalent to reducing a light exiting angle of thelarge-angle light. Therefore, the large-angle light emitted from thelight emitting device can also be emitted from the display panel tocontribute to the light emission of the pixels, thereby improving thelight extraction efficiency of the light emitting device and reducingpower consumption of the display panel. In the following,implementations of the present disclosure will be explained in detail.

FIG. 2 is a schematic top view of a part of a display panel according toan embodiment of the present disclosure, and FIG. 3 is a cross-sectionalschematic diagram at a position of a tangent line A-A′ in FIG. 2 .

As shown in FIG. 3 , the structure of the display panel is schematicallyillustrated. The display panel includes: a base substrate 101, a lightemitting device layer 102, and a light adjustment structure layer 103.The light emitting device layer 102 is disposed on the base substrate101, and the light emitting device layer 102 includes a plurality oflight emitting devices P (two are shown in FIG. 3 ), each of which maybe an organic light emitting device, a miniature diode, or the like. Thelight adjustment structure layer 103 is disposed at a side of the lightemitting device layer 102 facing away from the base substrate 101, andthe light adjustment structure layer 103 includes a plurality of lightadjustment units 31 and a dielectric layer 32 covering the plurality oflight adjustment units 31. The dielectric layer 32 may be onewhole-layer continuous film layer structure or a patterned film layer,and may include a plurality of dielectric units, one of which covers onelight adjustment unit 31. In FIG. 3 , a case where the dielectric layer32 is one whole-layer continuous film layer structure is illustrated. Arefractive index n11 of the light adjustment unit 31 is smaller than arefractive index n22 of the dielectric layer 32. Referring to FIG. 2 andFIG. 3 in conjunction, each of the light adjustment units 31 includes alight adjustment sub-section F and a through hole K. The through hole Kpenetrates the light adjustment unit 31 in a direction e perpendicularto the base substrate (when the display panel is a flat-plate displaypanel, the direction e perpendicular to the base substrate is the sameas a direction perpendicular to the display panel). The through hole Koverlaps the light emitting device P, and the light adjustmentsub-section F surrounds the through hole K. As shown in FIG. 3 , for onelight adjustment unit 31, in a direction from the through hole K to thelight adjustment sub-section F, a thickness of the light adjustmentsub-section F gradually increases, in such a manner that light emittedfrom the light emitting device P, after passing through the lightadjustment sub-section F, is deflected towards an upward direction ofthe direction e.

In the embodiment of the present disclosure, the light adjustmentstructure layer 103 is provided on the light emitting device P, and therefractive index n11 of the light adjustment unit 31 in the lightadjustment structure layer 103 is smaller than the refractive index n22of the dielectric layer 32, so that refraction occurs when the lightemitted from the light emitting device P is irradiated onto an interface(that is, on the interface) where the light adjustment unit 31 and thedielectric layer 32 are in contact with each other. As shown in asimplified light path diagram in FIG. 3 , light S1 emitted by the lightemitting device P is irradiated to the interface where the lightadjustment unit 31 and the dielectric layer 32 are in contact with eachother, an incidence angle of the light S1 is 01, and a refraction angleafter entering the dielectric layer 32 is 02. According to a law ofrefraction, n11*sin θ1=n22*sin θ2. Since n11<n22, then sin θ1>sin θ2 andthus θ1>θ2. That is, the incidence angle is larger than the refractionangle. After the light S1 is refracted at the interface between thelight adjustment unit 31 and the dielectric layer 32, the angle betweenthe propagation direction and the direction e becomes smaller, which isequivalent to reducing the light emission angle of the large-angle lightemitted by the light emitting device P. Similarly, light S2 also has itslight path changed after being refracted at the interface between thelight adjustment unit 31 and the dielectric layer 32. In the displaypanel according to the embodiment of the present disclosure, the lightadjustment structure layer can adjust the light path of the large-anglelight emitted by the light emitting device, to reduce the angle betweenthis part of the light and the direction perpendicular to the basesubstrate, so as to reduce a probability that this part of the lightwill be totally reflected at the interface between the film layers inthe display panel or at the interface between the display panel and theair, which can improve the light emission efficiency of the lightemitting device, thereby reducing the power consumption of the displaypanel.

With continued reference to FIG. 1 , the dielectric layer 32 is aplanarization layer. In the embodiment of the present disclosure, byproviding the light adjustment structure layer on the light emittingdevice, the light path of the large-angle light emitted by the lightemitting device can be adjusted, which reduces the angle between thelight and the direction perpendicular to the display panel, lowers theprobability that the light is totally reflected in the display panel andrestricted in the display panel, and improves the light emissionefficiency of the light emitting device. In addition, the dielectriclayer is a planarization layer, and the whole-layer planarization layermanufactured during manufacturing can cover all the light adjustmentunits, so that there is no need to etch the dielectric layer. Moreover,the planarization layer can provide a flattening surface for the lightadjustment structure layer, which is beneficial to flatness of the lightemitting surface side of the display panel.

Specifically, the interface between the light adjustment sub-section andthe dielectric layer is an arc-shaped surface, which may be either aconvex surface protruding from the light emitting device layer along adirection facing away from the base substrate or a concave surfaceformed by the light adjustment sub-section recessing towards to thelight emitting device layer. The interface between the light adjustmentsub-section and the dielectric layer is an arc-shaped surface, thennormal directions corresponding to different parts of the arc-shapedsurface are different, so that when the light of the same angle emittedby the light emitting device is irradiated to different parts of thearc-shaped surface, the light propagates in different directions afterbeing refracted. After the large-angle light emitted by the lightemitting device is refracted at the interface between the lightadjustment sub-section and the dielectric layer, the light can alsopropagate in many different directions while having the propagationdirection of the light changed, so as to ensure that the light isuniformly diverged and emitted while improving the light emissionefficiency of the light emitting device.

As shown in FIG. 3 , the interface between the light adjustmentsub-section F and the dielectric layer 32 is a convex surface thatprotrudes from the light emitting device layer 102 along a directionfacing away from the base substrate 101.

In another embodiment, as shown in FIG. 4 , which illustrates anothercross-sectional schematic diagram of a display panel according to anembodiment of the present disclosure, the interface between the lightadjustment sub-section F and the dielectric layer 32 is a concavesurface. The drawing illustrates the light S3 and the light S4 emittedfrom the light emitting device P at relatively large angles. Taking thelight S3 as an example, the incidence angle at the interface between thelight adjustment sub-section F and the dielectric layer 32 is 03, andthe refraction angle after entering the dielectric layer 32 is 04.According to the law of refraction, n11*sin θ3=n22*sin θ4. Sincen11<n22, then sin θ3>sin θ4, and thus θ3>θ4. That is, the angle betweenthe propagation direction and the direction e becomes smaller after thelight S3 is refracted at the interface between the light adjustmentsub-section F and the dielectric layer 32, thereby reducing theprobability that the light will be totally reflected in the displaypanel and thus restricted in the display panel.

As an example, the interface between the light adjustment sub-sectionand the dielectric layer can also be a slope surface. That is, in thecross-sectional schematic diagram, the interface between the lightadjustment sub-section and the dielectric layer is substantially astraight line.

In an embodiment, an orthographic projection of the light adjustmentunit 31 on the base substrate 101 has a ring shape. With continuedreference to the top view shown in FIG. 2 , the orthographic projectionof the light adjustment unit 31 on the base substrate 101 is obtainedalong a plan viewing direction. Then, in a top view, the lightadjustment unit 31 coincides with the orthographic projection (notlabelled in the drawing) of the light adjustment unit 31 on the basesubstrate 101, and it can be seen that the light adjustment unit 31 hasa ring shape in the top view. With continued reference to theillustration in FIG. 3 , the light adjustment unit 31 includes a firstsurface M1 facing away from the base substrate 101, and the firstsurface M1 protrudes along a direction facing away from the basesubstrate 101. In this embodiment, the light adjustment unit 31corresponds to a ring-shaped convex lens structure. The ring-shapedconvex lens has a through hole in a center, and the through holeoverlaps the light emitting device. An inner part of the ring-shapedconvex lens is the light adjustment sub-section. The relativelylarge-angle light emitted from the light emitting device is refracted atthe interface between the ring-shaped convex lens and the dielectriclayer after being emitted to the inner part of the ring-shaped convexlens, and the angle between the propagation direction of the light andthe direction perpendicular to the display panel becomes smaller afterthe refraction, so that the probability that the part of the light istotally reflected inside the display panel is lowered, thereby improvingthe light emission efficiency of the light emitting device. Whenmanufacturing, the light adjustment unit may be manufactured by aninkjet printing process, in which ink droplets are sprayed at acorresponding position of each light adjustment unit, an evaporationamount of solvent at an edge of the ink droplet is much larger than anamount of loss of a liquid volume thereof, so the solvent is replenishedfrom a central region to an edge, so as to form a capillary flow frominside to outside to make solute in the ink gather at the edge; thesolute in the ink is the manufacturing material of the light adjustmentunit, and after the solvent is evaporated, a light adjustment unithaving through holes is formed; and then a dielectric layer is formed onthe plurality of light adjustment units. A representative specificmanufacturing method will be described in detail in followingembodiments of the manufacturing method.

In FIG. 2 , a case where the orthographic projection of the lightadjustment unit 31 on the base substrate 101 is a circular ring isillustrated, while in another embodiment, the orthographic projection ofthe light adjustment unit 31 on the base substrate 101 may also be arectangular ring. In another embodiment, the shape of the lightadjustment unit 31 is substantially the same as a shape of an outer edgeof the light emitting device P in a top view. In one embodiment, FIG. 5illustrates another cross-sectional schematic diagram of a display panelaccording to an embodiment of the present disclosure. As shown in FIG. 5, an array layer 107 is further included on the base substrate 101, andthe array layer 107 includes a plurality of thin-film transistors T. Inthe drawing, the thin-film transistor T of a top gate structure is usedfor illustration. Alternatively, the thin-film transistor may be of abottom gate structure. The light emitting device P in the light emittingdevice layer 102 includes an anode 7, a light emitting layer 8 and acathode 9 that are sequentially stacked, and the thin-film transistor Tis connected to the anode 7. An encapsulation layer 104 is furtherprovided on the light emitting device layer 102, and the encapsulationlayer 104 includes two inorganic encapsulation layers w and one organicencapsulation layer y. The organic encapsulation layer y is locatedbetween the two inorganic encapsulation layers w. A light emittingmaterial in the light emitting layer 8 is sensitive to water and oxygen,and the encapsulation layer 104 can play a role in encapsulating andprotecting the light emitting device, to prevent damage by the water andoxygen and guarantee a service life of the light emitting device P. Inthe encapsulation layer 104, the inorganic encapsulation layer w hashigh compactness and can well block water and oxygen molecules, andorganic molecules in the organic encapsulation layer y have goodflexibility and can help the inorganic encapsulation layer w releasestress, so as to prevent the inorganic encapsulation layer w fromcracking. The light adjustment structure layer 103 is located at a sideof the encapsulation layer 104 facing away from the light emittingdevice layer 102.

In an embodiment, FIG. 6 illustrates another cross-sectional schematicdiagram of a display panel according to an embodiment of the presentdisclosure. As shown in FIG. 6 , the display panel includes anencapsulation layer 104 located between the light emitting device layer102 and the light adjustment structure layer 103. The light emittingdevice P is schematically illustrated in the drawing. The encapsulationlayer 104 includes at least one inorganic encapsulation layer w (twolayers are shown in the drawing) and at least one organic encapsulationlayer y (one layer is shown in the drawing). In the encapsulation layer104, the inorganic encapsulation layer w and the organic encapsulationlayer y are alternately stacked, and refractive indexes of the inorganicencapsulating layer w and the organic encapsulating layer y aredifferent. Generally, the refractive index of the organic encapsulatinglayer y is smaller than the refractive index of the inorganicencapsulating layer w. Then, after the light emitted by the lightemitting device P enters the encapsulation layer 104, some large-anglelight will be totally reflected at an interface between the organicencapsulation layer y and the inorganic encapsulation layer w (thesimplified light path diagram shown in the drawing) and thus can nolonger exit the display panel, which has a certain affection on thelight emission efficiency of the light emitting device. However,according to the present disclosure, the light adjustment structurelayer is provided at the side of the encapsulation layer facing awayfrom the light emitting device layer, the light emitted by the lightemitting device first enters the encapsulation layer and then exits fromthe encapsulation layer and then enters the light adjustment structurelayer, and the light adjustment structure layer can adjust thepropagation direction of at least some of the large-angle light enteringtherein, to prevent more large-angle light from being totally reflectedin the display panel and unable to exit the display panel, so as tolower the probability of total reflection of the light in the displaypanel and improve the light emission efficiency of the light emittingdevice.

Further, in some embodiments, the display panel further includes a touchfilm group layer. As shown in FIG. 7 , which illustrates anothercross-sectional schematic diagram of a display panel according to anembodiment of the present disclosure, the display panel includes anencapsulation layer 104 and a touch film group layer 105. Both theencapsulation layer 104 and the touch film group layer 105 are locatedbetween the light emitting device layer 102 and the light adjustmentstructure layer 103. The encapsulation layer 104 is located at a side ofthe touch film group layer 105 close to the light emitting device layer102, and includes at least one inorganic encapsulation layer w (twolayers are shown in the drawing) and at least one organic encapsulationlayer y (one layer is shown in the drawing). The touch film group layerin the drawing is a simplified illustration. Alternatively, the touchfilm group layer may include an electrode array composed of a pluralityof block-shaped touch electrodes. In the electrode array, a plurality ofblock-shaped touch electrodes are arranged in a row direction to form anelectrode row, and a plurality of block-shaped touch electrodes arearranged in a column direction to form an electrode column. Any twoadjacent block-shaped touch electrodes in one electrode row areelectrically connected, and any two adjacent block-shaped touchelectrodes in one electrode column are electrically connected. Anembodiment of the present disclosure provides a display panel having atouch function, and a touch film group layer is formed on theencapsulation layer. A thickness of the touch film group layer isrelatively thin, which is conducive to reduction of the overallthickness of the panel compared with an aspect where a touch film groupis bonded to the display panel. In addition, providing the lightadjustment structure layer at the side of the touch film group layerfacing away from the light emitting device layer can adjust the lightpath of the light that is emitted by the light emitting device and stillhas a relatively large light emission angle after passing through thetouch film group layer, to reduce the probability of total reflection oflight in the display panel and improve the light emission efficiency ofthe light emitting device.

In one embodiment, with continued reference to FIG. 2 , two adjacentlight adjustment units 31 are independent of each other. In thedirection perpendicular to the base substrate 101, the light emittingdevice P overlaps the through hole K of the light adjustment unit 31,that is, one light emitting device P corresponds to one light adjustmentunit 31. By setting two adjacent light adjustment units 31 independentlyof each other, the light adjustment sub-section in each light adjustmentunit can adjust large-angle light emitted by the light emitting unitcorresponding thereto, to avoid interference of light adjustment betweenadjacent light adjustment units.

In another embodiment, adjacent two light adjustment units of some lightadjustment units are in contact with each other. FIG. 8 illustratesanother cross-sectional schematic diagram of a display surface accordingto an embodiment of the present disclosure. As shown in FIG. 8 , thereare two adjacent light emitting devices P1 and P2, the light adjustmentunit 311 corresponds to the light emitting device P1, the lightadjustment unit 312 corresponds to the light emitting device P2, and thelight adjustment unit 311 is in contact with the light adjustment unit312. Due to a manufacturing process or limitations of a size of thelight adjustment unit, some adjacent light adjustment units in thedisplay panel are in contact with each other, as long as the throughhole of the light adjustment unit overlaps the light emitting device,that is, for one light adjustment unit, as long as a thickness of thelight adjustment sub-section surrounding the through hole graduallyincreases in the direction from the through hole towards the lightadjustment sub-section.

In some implementations, the plurality of light emitting devices in thedisplay panel according to the embodiment of the present disclosureincludes a first light emitting device and a second light emittingdevice that emit light of different colors, and a light emitting area ofthe first light emitting device is larger than that of the second lightemitting device. When the light emitting devices emit light of differentcolors, light emitting materials used in the light emitting devices aredifferent, and correspondingly, light emitting efficiencies of thedifferent light emitting materials are different. In the embodiments ofthe present disclosure, by adjusting a light emitting area of a lightemitting device, an affection on the light emitting brightness by thelight emission efficiency of the light emitting device is balanced. Tobe specific, a light emission efficiency of the first light emittingdevice is smaller than that of the second light emitting device, and thelight emitting area of the first light emitting device is set to belarger than that of the second light emitting device, in order toachieve that the light emitting devices emitting light of differentcolors cooperate with each other to perform color display.

The plurality of light emitting devices includes a red light emittingdevice, a green light emitting device, and a blue light emitting device.In one embodiment, a light emitting area of the blue light emittingdevice is larger than that of the red light emitting device, a lightemitting area of the blue light emitting device is larger than that ofthe green light emitting device, and a light emitting area of the greenlight emitting device is larger than that of the red light emittingdevice. In another embodiment, the light emitting area of the blue lightemitting device is larger than that of the red light emitting device,the light emitting area of the blue light emitting device is larger thanthat of the green light emitting device, and the light emitting area ofthe green light emitting device is equal to that of the red lightemitting device. Since a difference between the light emissionefficiency of the green light emitting device and the light emissionefficiency of the red light emitting device is relatively small, settingthe light emitting areas of the green light emitting device and the redlight emitting device to be equal has little effect on the displayeffect, while a difference between the light emission efficiency of theblue light emitting device and the light emitting efficiencies of thered light emitting device and the green light emitting device isrelatively large, so a differential design is made to the light emittingarea of the blue light emitting device.

In an embodiment, FIG. 9 illustrates another schematic top diagram of apart of a display panel according to an embodiment of the presentdisclosure, FIG. 10 illustrates a cross-sectional schematic diagram atthe position of the tangent line BB′ in FIG. 9 , and FIG. 11 illustratesa schematic diagram of the principle of the corresponding embodiment inFIG. 10 .

As shown in FIG. 9 , a first light emitting device Pa and a second lightemitting device Pb emitting light of different colors are shown, a lightemitting area of the first light emitting device Pa is larger than thatof the second light emitting device Pb, the plurality of lightadjustment units includes a first light adjustment unit 31 a and asecond light adjustment unit 31 b, the first light adjustment unit 31 aincludes a first through hole K1 and a first light adjustmentsub-section F1 surrounding the first through hole K1, and the secondlight adjustment unit 31 b includes a second through hole K2 and asecond light adjustment sub-section F2 surrounding the second throughhole K2. The first light emitting device Pa overlaps the first throughhole K1, and the second light emitting device Pb overlaps the secondthrough hole K2. That is, the first light emitting device Pa correspondsto the first light adjustment unit 31 a, and the second light emittingdevice Pb corresponds to the second light adjustment unit 31 b.

As shown in FIG. 10 , for one first light adjustment unit 31 a, in adirection from the first through hole K1 to the first light adjustmentsub-section F1, a thickness change rate of the first light adjustmentsub-section F1 is γ1, and for one second light adjustment unit 31 b, ina direction from the second through hole K2 to the second lightadjustment sub-section F2, a thickness change rate of the second lightadjustment sub-section F2 is γ2, where γ2>γ1. The thickness change rateis understood to be a ratio of an amount of change in the thickness ofthe light adjustment sub-section to an amount of change in the length ofthe light adjustment sub-section. The amount of increase in the lengthof the light adjustment sub-section is the amount of change in thelength of the light adjustment sub-section in the direction from thefirst through hole to the first light adjustment sub-section in thecross-sectional diagram, and the amount of change in the thickness ofthe light adjustment sub-section is the amount of change in thethickness of the light adjustment sub-section in the direction e in thecross-sectional diagram.

As shown in the simplified schematic diagram in FIGS. 11 , J1 and J2represent two light adjustment sub-sections having different thicknesschange rates. In the cross-sectional diagram, at positions from a pointC to a point D in the drawing, the thickness change rate of the lightadjustment sub-section J2 is larger than the thickness change rate ofthe light adjustment sub-section J1, with a line passing through thepoint D and parallel to the direction e (that is, the directionperpendicular to the base substrate) as a boundary. Light S5 emittedfrom the light emitting device P is emitted to an intersection of thelight adjustment sub-section J1 and the boundary, and the light S5 canbe refracted at an interface between the light adjustment sub-section J1and the dielectric layer to change the light path. Light S6 emitted bythe light emitting device P is emitted to an intersection of the lightadjustment sub-section J2 and the boundary, and the light S6 can berefracted at an interface between the light adjustment sub-section J2and the dielectric layer to change the light path. An angle between thelight S5 and the direction e is β2, and an angle between the light S6and the direction e is β1, where β1<β2. That is, the light adjustmentsub-section J2 cannot play a role of changing the light path of thelight S5, and the relatively large-angle light emitted by the lightemitting device P is more likely to be changed in the light path by thelight adjustment sub-section having a relatively small thickness changerate. Therefore, in the embodiment of the present disclosure, it is setγ2>γ1, and the first light adjustment sub-section can change the lightpath for more large-angle light compared with the second lightadjustment sub-section, that is, the first light adjustment sub-sectionhas a more obvious effect on improving the light emission efficiency ofthe light emitting device compared with the second light adjustmentsub-section. The first light adjustment sub-section corresponds to thefirst light emitting device having a relatively large light emittingarea, and the difference in light emission efficiency between the firstlight emitting device and the second light emitting device can befurther balanced, thereby improving the display effect of the displaypanel.

Specifically, in one embodiment, the light emitting area of the bluelight emitting device>the light emitting area of the green lightemitting device>the light emitting area of the red light emittingdevice. FIG. 12 illustrates another cross-sectional schematic diagram ofa display panel according to an embodiment of the present disclosure. Asshown in FIG. 12 , a blue light emitting device PB corresponds to alight adjustment unit 31B, and the light adjustment unit 31B includes alight adjustment sub-section FB; a green light emitting device PGcorresponds to a light adjustment unit 31G, and the light adjustmentunit 31G includes a light adjustment sub-section FG; and a red lightemitting device PR corresponds to a light adjustment unit 31R, and thelight adjustment unit 31R includes a light adjustment sub-section FR.For one light adjustment unit, in a direction from the through hole tothe light adjustment sub-section, a thickness change rate of the lightadjustment sub-section FB is the smallest, and a thickness change rateof the light adjustment sub-section FR is the largest. Therefore, amongthe light adjustment sub-sections corresponding to the light emittingdevices of three colors, the light adjustment sub-section FB can changethe light path of the more large-angle light, the light adjustmentsub-section FB has the greatest effect on improving the light emissionefficiency of the blue light emitting device PB, the light adjustmentsub-section FR has the smallest effect on improving the light emissionefficiency of the red light emitting device PR, and the light adjustmentsub-section FG has a medium role in improving the light emissionefficiency of the green light emitting device PG. Through performingdifferent designs on the light adjustment sub-sections corresponding tothe light emitting devices having three colors, the difference in lightemission efficiency between different light emitting devices can also bebalanced while ensuring the improvement of the light emission efficiencyof the light emitting device of each color, so as to improve the displayeffect of the display panel.

In another embodiment, the light emitting area of the green lightemitting device and the light emitting area of the red light emittingdevice are the same, and both are smaller than the light emitting areaof the blue light emitting device. For one light adjustment unit, in thedirection from the through hole to the light adjustment sub-section, thethickness change rate of the light adjustment sub-section correspondingto the green light emitting device is equal to the thickness change rateof the light adjustment sub-section corresponding to the red lightemitting device, and both are larger than the thickness change rate ofthe light adjustment sub-section corresponding to the blue lightemitting device. The light emission efficiency of the blue lightemitting device is quite different from that of the red and green lightemitting devices, and in this embodiment, differential designs are madeto the light emitting area of the blue light emitting device and thecorresponding light adjustment sub-section.

FIG. 13 illustrates another cross-sectional schematic diagram of adisplay panel according to an embodiment of the present disclosure. FIG.14 illustrates another simplified cross-sectional diagram of a displaypanel according to an embodiment of the present disclosure. As shown inFIG. 13 , the first light adjustment unit 31 a corresponds to the firstlight emitting device Pa, the second light adjustment unit 31 bcorresponds to the second light emitting device Pb, the first lightemitting device Pa and the second light emitting device Pb emit light ofdifferent colors, and the light emitting area of the first lightemitting device Pa is larger than that of the second light emittingdevice Pb. The minimum distance from an inner side of the first lightadjustment unit 31 a to an outer edge of the first light emitting devicePa is a first distance h1, the minimum distance from an inner side ofthe second light adjustment unit 31 b to an outer edge of the secondlight emitting device Pb is a second distance h2, and the first distanceh1 is larger than the second distance h2. The first light emittingdevice Pa and the second light emitting device Pb are substantially atthe same plane height, and the first light adjustment unit 31 a and thesecond light adjustment unit 31 b are also basically at the same planeheight, so that as illustrated in the drawing, in the cross-sectionaldiagram, a horizontal distance from the inner side of the first lightadjustment unit 31 a to the outer edge of the first light emittingdevice Pa is h1, a horizontal distance from the inner side of the secondlight adjustment unit 31 b to the outer edge of the second lightemitting device Pb is h2, light that is emitted from the edge of thefirst light emitting device Pa (e.g., only such light) and has a lightemission angle larger than α1 can be adjusted by the first lightadjustment unit to change the light path, and light that is emitted fromthe edge of the second light emitting device Pb (e.g., only such light)and has a light emission angle larger than α2 can be adjusted by thesecond light adjustment unit to change the light path, where h1>h2 andthus α1>α2. Compared with the first light adjustment unit 31 a, thesecond light adjustment unit 31 b can adjust the light path for morelight emitted by the second light emitting device Pb. That is, after thelight path is changed at the interface between the second lightadjustment unit 31 b and the dielectric layer, more light emitted by thesecond light emitting device Pb approaches the second light emittingdevice PB, so that an amount of the increase in the light emissionefficiency of the second light emitting device is larger than an amountof the increase in the light emission efficiency of the first lightemitting device.

This embodiment can be applied to a display panel having an arc-shapedside surface. As shown in FIG. 14 , the display panel having thearc-shaped side surface (a position Q in the drawing) is simplyillustrated, and a specific structure is not shown. Since the side ofthe display panel is bent, light emitted by the bent portion during thelight emitting period will be shifted relative to a front viewingdirection f of the display panel. Herein, the front viewing direction fis understood as the direction in which a user's eyes look towards thedisplay panel when the user is using the display panel. When the userviews the arc-shaped side surface (the Q position) in the front viewingdirection f, there is a color shift phenomenon, which affects thedisplay effect. This is caused by different degrees of attenuation oflight emitted by light emitting devices of different colors in a displayregion of the arc-shaped side surface. According to the embodiment ofFIG. 13 , in the display region of the arc-shaped side surface,different designs are made to the light adjustment units correspondingto the light emitting devices of different colors, and a difference inamounts of the increase in light emission efficiency of the lightemitting devices of different colors is adjusted to balance thedifference in the degrees of attenuation of light emitted by the lightemitting devices of different colors, the color shift of the arc-shapedside surface can be improved, and the display effect can be improved.

Specifically, in the display region of the arc-shaped side surface, aminimum distance from the inner side of the light adjustment unitcorresponding to the blue light emitting device to the outer edge of theblue light emitting device is h3, a minimum distance from the inner sideof the light adjustment unit corresponding to the green light emittingdevice to the outer edge of the green light emitting device is h4, and aminimum distance from the inner side of the light adjustment unitcorresponding to the red light emitting device to the outer edge of thered light emitting device is h5. In one embodiment, h3>h4>h5. In anotherembodiment, h3>h4=h5.

In an embodiment, the first light emitting device and the second lightemitting device emit light of different colors, and the light emittingarea of the first light emitting device is larger than the lightemitting area of the second light emitting device. An area of thethrough hole overlapping the first light emitting device is a firstarea, an area of the through hole overlapping the second light emittingdevice is a second area, and the first area is larger than the secondarea. The area of the through hole overlapping the light emitting devicemay be designed based on a difference in the light emitting area, andthe larger light emitting area of the light emitting device leads to thelarger area of the through hole overlapping the light emitting device.In this way, the size of the through hole of the light adjustment unitmay be designed so as to adapt to the light emitting area of the lightemitting device, which can ensure that the light adjustment structurelayer adjusts (e.g., only adjusts) the light path of the relativelylarge-angle light emitted by the light emitting device without changingthe light path of the relatively small-angle light emitted by the lightemitting device, thereby avoiding adverse effects caused by adjustingthe light path of the relatively small-angle light.

FIG. 15 illustrates another schematic top diagram of a display panelaccording to an embodiment of the present disclosure. As shown in FIG.15 , the plurality of light emitting devices includes a red lightemitting device, a green light emitting device and a blue light emittingdevice, and a light emitting area of the blue light emitting device PB>alight emitting area of the green light emitting device PG>a lightemitting area of the red light emitting device PR. The through hole KBoverlaps the blue light emitting device PB, the through hole KG overlapsthe green light emitting device PG, the through hole KR overlaps the redlight emitting device PR, and an area of the through hole KB>an area ofthe through hole KG>an area of the through hole KR. It may be designedthat the areas of the corresponding through holes of the light emittingdevices of different colors are different, in order to ensure that apart of large-angle light emitted by each of light emitting devices ofdifferent colors can have its light path changed after action of thelight adjustment structure layer, thereby improving the light emissionefficiency of each of the light emitting devices of different colors.

In another embodiment, the light emitting area of the green lightemitting device and the light emitting area of the red light emittingdevice are the same and are both smaller than the light emitting area ofthe blue light emitting device, the area of the through hole overlappingthe blue light emitting device is larger than the area of the throughhole overlapping the green light emitting device, the area of thethrough hole overlapping the blue light emitting device is larger thanthe area of the through hole overlapping the red light emitting device,and the area of the through hole overlapping the red light emittingdevice is equal to the area of the through hole overlapping the greenlight emitting device. These will not be illustrated in the drawingsagain.

FIG. 16 illustrates another cross-sectional schematic diagram of adisplay panel according to an embodiment of the present disclosure. Asshown in FIG. 16 , the display panel further includes a contact layer106 located between the light emitting device layer 102 and the lightadjustment structure layer 103. A surface on a side of the contact layer106 facing away from the base substrate 101 includes a plurality ofcentral regions X and a peripheral region Z surrounding the centralregions X, the light adjustment unit 31 is in contact with theperipheral region Z, and the through hole K exposes the central regionX. That is, a shape of the central region X is substantially the same asa shape of the through hole K, while a shape of the peripheral region Zis substantially the same as the shape of the light adjustment unit 31.

Specifically, in one embodiment, the central region X has a smallersurface energy than the peripheral region Z. In this embodiment, thelight adjustment unit in the light adjustment structure layer can bemanufactured using the inkjet printing process. During the manufacturingprocess, first, a surface of the contact layer facing away from the basesubstrate is pretreated, to form a plurality of central regions and aplurality of peripheral regions, and the surface energy of the centralregion is smaller than that of the peripheral region; then the inkjetprinting process is used to spray ink droplets at a positioncorresponding to the light emitting device, the ink droplets cover thecentral regions and at least part of the peripheral regions, it isuneasy for the central region to be wetted by the ink droplets since thesurface energy of the central region is smaller than that of theperipheral region, and it is more easily for the peripheral region to bewetted by the ink droplets than the central region; and duringevaporation of solvent in the ink droplets, ink in the central region ismore likely to gather towards the peripheral region, a light adjustmentunit having a through hole is formed after the solvent is evaporated,and the through hole exposes the central region. A differential designof the surface energy of the central region and the surface energy ofthe peripheral region in the contact layer can play an auxiliary role inthe process of manufacturing the light adjustment unit, and it ispossible to manufacture the light adjustment unit having the throughhole by the inkjet printing process with a single step. In addition, adifference between the surface energy of the central region and theperipheral region can be adjusted by adjusting pretreatment processparameters, so as to control an area of the through hole in the lightadjustment unit.

Specifically, in another embodiment, the central region X has a smallerroughness than the peripheral region Z. In this embodiment, the lightadjustment unit in the light adjustment structure layer can bemanufactured using the inkjet printing process. During the manufacturingprocess, first, a surface of the contact layer facing away from the basesubstrate is pretreated, to form a plurality of central regions and aplurality of peripheral regions, and the roughness of the central regionis smaller than that of the peripheral region; then the inkjet printingprocess is used to spray the ink droplets at the position correspondingto the light emitting device, the ink droplets cover the central regionsand at least part of the peripheral regions, since the roughness of thecentral region is smaller than that of the peripheral region, that is, asurface of the central region is smoother than that of the peripheralregion, it is uneasy for the central region to be wetted by the inkdroplets, while it is more easily for the peripheral region to be wettedby the ink droplets; and during evaporation of the solvent in the inkdroplets, ink in the central region is more likely to gather towards theperipheral region, a light adjustment unit having a through hole isformed after the solvent is evaporated, and the through hole exposes thecentral region. A differential design of the roughness of the centralregion and the roughness of the peripheral region in the contact layercan play an auxiliary role in the process of manufacturing the lightadjustment unit, and it is possible to manufacture the light adjustmentunit having the through hole by the inkjet printing process with asingle step. In addition, a difference between the roughness of thecentral region and the peripheral region can be adjusted by adjustingpretreatment process parameters, so as to control the area of thethrough hole in the light adjustment unit. As an example, the contactlayer is a nanocrystalline layer, in which a density of nanoparticles inthe nanocrystalline layer in the central region is larger than a densityof nanoparticles in the peripheral region.

FIG. 17 illustrates another cross-sectional schematic diagram of adisplay panel according to an embodiment of the present disclosure. Asshown in FIG. 17 , the first light emitting device Pa and the secondlight emitting device Pb that emit light of different colors are shown,a light emitting area of the first light emitting device Pa is largerthan that of the second light emitting device Pb, and the plurality ofcentral regions includes a first central region X1 and a second centralregion X2. In the direction e perpendicular to the base substrate 101,the first central region X1 and the first light emitting device Paoverlap each other, and the second central region X2 and the secondlight emitting device Pb overlap each other.

In one embodiment, the first central region X1 has a smaller surfaceenergy than the second central region X2. The smaller surface energyleads to that it is less likely to be wetted by the ink droplets whenmanufacturing the light adjustment unit by the inkjet printing process.Then, during the evaporation of the ink solvent during manufacturing,the ink on the first central region is more likely to gather towards theperipheral region than the ink on the second central region. In otherwords, more ink on the first central region gathers towards theperipheral region. Correspondingly, after the evaporation of the solventis completed, the area of the through hole formed on the first centralregion is larger. By setting the surface energy of the central regionscorresponding to the light emitting devices emitting light of differentcolors to be different, it is possible to manufacture, by means of theinkjet printing process, light adjustment units having through holeswith different areas on the light emitting devices emitting light ofdifferent colors, so as to design the size of the through hole of thelight adjustment unit to adapt to the light emitting area of the lightemitting device. A differential design on the surface energy of thecentral regions corresponding to light emitting devices emitting lightof different colors can play an auxiliary role in the manufacturing ofthe light adjustment unit.

Specifically, in an embodiment, the light emitting area of the bluelight emitting device is larger than the light emitting area of thegreen light emitting device, and the light emitting area of the greenlight emitting device is larger than that of the red light emittingdevice; the surface energy of the central region overlapping the bluelight emitting device is smaller than the surface energy of the centralregion overlapping the green light emitting device, and the surfaceenergy of the central region overlapping the green light emitting deviceis smaller than the surface energy of the central region overlapping thered light emitting device.

In another embodiment, the light emitting area of the green lightemitting device is the same as that of the red light emitting device,and both are smaller than the light emitting area of the blue lightemitting device; the surface energy of the central region overlappingthe blue light emitting device is smaller than the surface energy of thecentral region overlapping the green light emitting device, and thesurface energy of the central region overlapping the green lightemitting device is equal to the surface energy of the central regionoverlapping the red light emitting device.

In another embodiment, the roughness of the first central region X1 issmaller than the roughness of the second central region X2. The smallerthe roughness, the less likely it is to be wetted by the ink dropletswhen manufacturing the light adjustment unit by the inkjet printingprocess. Then, during the evaporation of the ink solvent duringmanufacturing, the ink on the first central region is more likely togather towards the peripheral region with respect to the ink on thesecond central region. In other words, the more ink on the first centralregion gathers towards the peripheral region. Correspondingly, after theevaporation of the solvent is completed, the area of the through holeformed on the first central region is larger. By setting the surfaceenergy of the central regions corresponding to the light emittingdevices emitting light of different colors to be different, it ispossible to manufacture, by means of the inkjet printing process, alight adjustment unit having through holes with different areas on thelight emitting devices emitting light of different colors, so as todesign the size of the through hole of the light adjustment unit toadapt to the light emitting area of the light emitting device. Adifferential design on the roughness of the central regionscorresponding to light emitting devices emitting light of differentcolors can assist the manufacturing of the light adjustment unit.

Specifically, in an embodiment, the light emitting area of the bluelight emitting device is larger than the light emitting area of thegreen light emitting device, and the light emitting area of the greenlight emitting device is larger than that of the red light emittingdevice; the roughness of the central region overlapping the blue lightemitting device is smaller than the roughness of the central regionoverlapping the green light emitting device, and the roughness of thecentral region overlapping the green light emitting device is smallerthan the roughness of the central region overlapping the red lightemitting device.

In another embodiment, the light emitting area of the green lightemitting device is the same as the light emitting area of the red lightemitting device, and both are smaller than the light emitting area ofthe blue light emitting device; the roughness of the central regionoverlapping the blue light emitting device is smaller than the roughnessof the central region overlapping the green light emitting device, andthe roughness of the central region overlapping the green light emittingdevice is equal to the roughness of the central region overlapping thered light emitting device.

FIG. 18 illustrates another cross-sectional schematic diagram of adisplay panel according to an embodiment of the present disclosure. FIG.19 illustrates a schematic diagram of a principle of the correspondingembodiment in FIG. 18 . As shown in FIG. 18 , a first light emittingdevice Pa and a second light emitting device Pb that emit light ofdifferent colors are shown, a light emitting area of the first lightemitting device Pa is larger than that of the second light emittingdevice Pb, a refractive index of a light adjustment unit 31 acorresponding to the first light emitting device Pa is n1, and arefractive index of a light adjustment unit 31 b corresponding to thesecond light emitting device Pb is n2, where n1<n2.

As shown in the simplified schematic diagram of FIG. 19 , one lightemitting device P and an interface M between the light adjustment unitand the dielectric layer are illustrated, and the dielectric layer has afixed refractive index. An incidence angle of light S7 to the interfaceM is θ5, and according to the law of refraction, when the refractiveindex of the light adjustment unit is n1 and refracted light of thelight S7 is S8′, the refraction angle is θ6; and when the refractiveindex of the light adjustment unit is n2 and the refracted light of thelight S7 is S8″, the refraction angle is θ7. Since n1<n2, then θ6<θ7. Itcan also be seen from the drawing that an angle between a propagationdirection of the light S8′ and the direction e is smaller than an anglebetween a propagation direction of the light S8″ and the direction e. Asa result, the smaller refractive index of the light adjustment unitleads to the smaller angle between the refracted light exiting from itsinterface with the dielectric layer and the direction e. That is, thesmaller refractive index of the light adjustment unit leads to thebetter performance in adjusting the light path of the large-angle lightemitted by the light emitting device. In the embodiment of the presentdisclosure, n1<n2, and thus the performance of the light adjustment unit31 a in adjusting the light path of the large-angle light is better thanthat of the light adjustment unit 31 b, so that the amount of theincrease in the light emission efficiency of the first light emittingdevice Pa is larger than the amount of the increase in the lightemission efficiency of the second light emitting device Pb. Then, thedifference in the light emission efficiency between the light emittingdevices of different colors can be balanced by adjusting the amount ofthe increase in the light emission efficiency of the light emittingdevices of different colors.

In an embodiment, the light emitting area of the blue light emittingdevice is larger than that of the green light emitting device, and thelight emitting area of the green light emitting device is larger thanthat of the red light emitting device; the refractive index of the lightadjustment unit corresponding to the blue light emitting device issmaller than the refractive index of the light adjustment unitcorresponding to the green light emitting device, and the refractiveindex of the light adjustment unit corresponding to the green lightemitting device is smaller than the refractive index of the lightadjustment unit corresponding to the red light emitting device.

In another embodiment, the light emitting area of the green lightemitting device is the same as that of the red light emitting device,and both are smaller than the light emitting area of the blue lightemitting device; the refractive index of the light adjustment unitcorresponding to the blue light emitting device is smaller than therefractive index of the light adjustment unit corresponding to the greenlight emitting device, and the refractive index of the light adjustmentunit corresponding to the green light emitting device is equal to therefractive index of the light adjustment unit corresponding to the redlight emitting device.

In another embodiment, the refractive index of the light adjustment unitcorresponding to the blue light emitting device is smaller than therefractive index of the light adjustment unit corresponding to the greenlight emitting device, and the refractive index of the light adjustmentunit corresponding to the green light emitting device is smaller thanthe refractive index of the light adjustment unit corresponding to thered light emitting device. The difference in light emission efficiencybetween light emitting devices of different colors can be balanced byadjusting the amount of the increase in the light emission efficiency oflight emitting devices of different colors, and the light emitting areaof the blue light emitting device, and the light emitting area of thered light emitting device and the light emitting area of the green lightemitting device in this embodiment can be further set to be identical.In view of this, the light emitting devices of different colors can bemanufactured using the same set of masks during the manufacturingprocess, so that the manufacturing process can be simplified.

Further, in some embodiments, after improving the light emissionefficiency of the blue light emitting device by adjusting the refractiveindex of the light adjustment unit corresponding to the blue lightemitting device, a light emitting brightness of the blue light emittingdevice can be reduced accordingly, so that the service life of the bluelight emitting device can be increased.

It should be noted that the embodiments of the present disclosure do notmake any limitation on the arrangement manner of the light emittingdevices in the display panel, and the arrangement of the light emittingdevices in the top view involved in a part of the above embodiments isrepresentative.

Based on the same inventive concept, the embodiments of the presentdisclosure further provide a display apparatus. FIG. 20 illustrates aschematic diagram of a display apparatus according to an embodiment ofthe present disclosure. As shown in FIG. 20 , the display apparatusincludes the display panel 10 according to any embodiment of the presentdisclosure. The display apparatus shown in FIG. 20 is forrepresentative, and the display apparatus may be any electronic devicehaving a display function, such as an on-board display apparatus, amobile phone, a tablet computer, a notebook computer, an electronicpaper book or a TV, a wearable mobile phone, or a watch.

Based on the same inventive concept, the embodiments of the presentdisclosure further provide a manufacturing method of a display panel,for manufacturing the display panel according to the embodiment of thepresent disclosure. FIG. 21 illustrates a first flowchart of amanufacturing method of a display panel according to an embodiment ofthe present disclosure, and FIG. 22 illustrates a second flowchart of amanufacturing method of a display panel according to an embodiment ofthe present disclosure. As shown in FIG. 21 , the manufacturing methodincludes steps as follows.

At step S101, a base substrate 101 is provided.

At step S102, a light emitting device layer 102 is formed on the basesubstrate 101. The light emitting device layer 102 includes a pluralityof light emitting devices P (two are shown for illustration), each ofwhich may be an organic light emitting device, a miniature diode, or thelike.

A light adjustment structure layer 103 is formed at a side of the lightemitting device layer 102 facing away from the base substrate 101. Thisprocess may be completely by steps S103 and S104 in the following.

At step S103, a plurality of light adjustment unit precursor T is formedby an inkjet printing process.

At step S104, solvent is evaporated to obtain a plurality of lightadjustment units 31. Each of the light adjustment units 31 includes alight adjustment sub-section F and a through hole K penetrating thelight adjustment unit 31 in a direction e perpendicular to the basesubstrate. The through hole K overlaps the light emitting device P, andthe light adjustment sub-section F surrounds the through hole K. For onelight adjustment unit 31, a thickness of the light adjustmentsub-section F gradually increases in a direction from the through-hole Ktowards the light adjustment sub-section F.

FIG. 22 is a schematic top view showing a partial region from step S103to step S104 during the manufacturing process. The light adjustment unit31 may be manufactured by an inkjet printing process, in which inkdroplets are sprayed at a position corresponding to each lightadjustment unit 31 (i.e., in a process of manufacturing the lightadjustment unit precursor T), an evaporation amount of solvent at anedge of the ink droplet is much larger than an amount of loss of aliquid volume thereof, so the solvent is replenished from a centralregion to an edge, so as to form a capillary flow from inside to outsideto make solute in the ink gather at the edge, and after the solvent isevaporated, the light adjustment unit 31 having through holes is formed.Moreover, the solute of the ink is the manufacturing material of thelight adjustment unit.

As an example, a composition of the ink used in inkjet printing can alsobe adjusted during manufacturing, in order to reduce surface tension ofthe ink. Therefore, during the evaporation of the solvent. In view ofthis, it is more easily for the solvent in the adjustment unit precursorT to be replenished from the central region to the edge, so that thesolute can gather at the edge.

At step S105, a dielectric layer 32 is formed on the plurality of lightadjustment units 31. The light adjustment unit has a smaller refractiveindex than the dielectric layer 32. The dielectric layer 32 and theplurality of light adjustment units 31 together constitute the lightadjustment structure layer 103.

In the manufacturing method according to this embodiment, first of all,the light adjustment unit precursor is formed by the inkjet printingprocess, and during the evaporation of the solvent in the ink, the inkin the central region of the light adjustment unit precursor isreplenished to the edge, so that the solute in the ink gathers at theedge of the adjustment unit precursor; after the solvent is evaporated,a light adjustment unit having through holes is formed; then thedielectric layer is formed on the light adjustment unit, to finally formthe light adjustment structure layer composed of the dielectric layerand the plurality of light adjustment units. The refractive index of thelight adjustment unit is smaller than the refractive index of thedielectric layer. In addition, for the display panel manufactured inthis manner, the light adjustment structure layer is formed on the lightemitting device layer, so that the light path of the large-angle lightemitted by the light emitting device can be adjusted to reduce the anglebetween this part of light and the direction perpendicular to thedisplay panel, thereby reducing the chance that this part of the lightwill be totally reflected at the interface of the film layers in thedisplay panel or at the interface between the display panel and the air.This can improve the light emission efficiency of the light emittingdevice, and thus the power consumption of the display panel can bereduced.

In an embodiment, FIG. 23 illustrates a third flowchart of amanufacturing method of a display panel according to an embodiment ofthe present disclosure. As shown in FIG. 23 , the manufacturing methodincludes steps as follows.

At step S201, a base substrate is provided.

At step S202, a light emitting device layer is formed on the basesubstrate. The light emitting device layer includes a plurality of lightemitting devices.

At step S203, a pre-contact layer is formed on the light emitting devicelayer.

At step S204, a surface of the pre-contact layer facing away from thebase substrate is pretreated to form a contact layer. The contact layerincludes a plurality of central regions and a peripheral regionsurrounding the central regions, and the central region overlaps thelight emitting device in a direction perpendicular to the basesubstrate. The central regions and the peripheral region formed afterthe pretreating have different characteristics. For example, the surfaceenergy of the central region is smaller than the surface energy of theperipheral region, or the roughness of the central region is smallerthan the roughness of the peripheral region.

At step S205, a plurality of light adjustment unit precursors is formedon the pre-contact layer by an inkjet printing process.

At step S206, solvent is evaporated to obtain a plurality of lightadjustment units. Each of the light adjustment units includes a lightadjustment sub-section and a through hole penetrating the lightadjustment unit in a direction perpendicular to the base substrate. Thethrough hole overlaps the light emitting device. The light adjustmentsub-section surrounds the through hole. For one of the light adjustmentunits, a thickness of the light adjustment sub-section graduallyincreases in a direction from the through hole to the light adjustmentsub-section.

At step S207, a dielectric layer is formed on the plurality of lightadjustment units. The light adjustment unit has a smaller refractiveindex than the dielectric layer.

For the display panel manufactured in this manner, reference may be madeto the schematic diagrams in FIG. 15 and FIG. 16 described above. Inthis embodiment, before manufacturing the light adjustment structurelayer, the pre-contact layer is first formed, and the surface of thepre-contact layer facing away from the base substrate is pretreated toform the contact layer. Correspondingly, a central region and aperipheral region that have different characteristics are formed in thecontact layer, and the difference in characteristics between the centralregion and the peripheral region can be considered in the formation ofthe light adjustment unit.

Further, step S205 uses the inkjet printing process to form theplurality of light adjustment unit precursors in such a manner that theplurality of light adjustment unit precursors covers the central regionand at least part of the peripheral region. This embodiment can ensurethat the through hole of the light adjustment unit formed after theevaporation of the solvent in the light adjustment unit precursoroverlaps the light emitting device, and in the direction perpendicularto the base substrate, the light adjustment unit does not overlap thelight emitting device, so as to ensure that the light adjustmentstructure layer adjusts the light path of the relatively large-anglelight emitted by the light emitting device (e.g., adjusts only such alight path) without changing the light path of the relativelysmall-angle light emitted by the light emitting device. This can avoidadverse effects after adjusting the light path of the relativelysmall-angle light.

In one embodiment, the surface energy of the central region is smallerthan the surface energy of the peripheral region, and after the lightadjustment unit precursor is formed by the inkjet printing process, itis uneasy for the central region to be wetted by ink droplets, while theperipheral region is more easily wetted by ink droplets than the centralregion. During the evaporation of the solvent in the light adjustmentunit precursor, the ink in the central region is more likely to gathertowards the peripheral region. After the solvent evaporates, a lightadjustment unit having through holes is formed. After the pretreating, acentral region and a peripheral region that have different surfaceenergy are formed, which can play an auxiliary role in the process ofmanufacturing the light adjustment unit. In addition, a differencebetween the surface energy of the central region and the surface energyof the peripheral region can be adjusted by adjusting pretreatmentprocess parameters, so as to control an area of the through hole in thelight adjustment unit. In the display panel, the plurality of lightemitting devices includes a red light emitting device, a green lightemitting device, and a blue light emitting device. In this way, thethrough holes overlapping the light emitting devices of different colorscan be formed to have different areas based on design requirements.

Specifically, step S204 pretreats the surface of the pre-contact layerfacing away from the base substrate to form the contact layer by thefollowing process.

The pretreating of the surface of the pre-contact layer may be performedby using a plasma treatment process to form a plurality of centralregions and a peripheral region. The plasma treatment process canincrease the surface energy of the surface of the film layer. Thesurface of the pre-contact layer is divided into a first pretreatmentregion and a second pretreatment region. In the direction perpendicularto the base substrate, the first pretreatment region overlaps the lightemitting device, and the second pretreatment region surrounds the firstpretreatment region. The plasma treatment process is used to pretreatthe second pretreatment region (e.g., only the second pretreatmentregion) to form the peripheral region while increasing the surfaceenergy, and the first pretreatment region forms the central regionwithout the pretreatment.

The pretreating of the surface of the pre-contact layer may be performedby an AUV process to form a plurality of central regions and aperipheral region. The UV process can increase the surface energy of thesurface of the film layer. The surface of the pre-contact layer isdivided into a first pretreatment region and a second pretreatmentregion. In the direction perpendicular to the base substrate, the firstpretreatment region overlaps the light emitting device, and the secondpretreatment region surrounds the first pretreatment region. The UVprocess is used to pretreat the second pretreatment region (e.g., onlyto pretreat the second pretreatment region) to form a peripheral regionwhile increasing the surface energy, and the first pretreatment regionforms the central region without the pretreatment.

The pretreating of the surface of the pre-contact layer may be performedby a hydrophilic or hydrophobic process to form a plurality of centralregions and a peripheral region. The surface of the pre-contact layer isdivided into a first pretreatment region and a second pretreatmentregion. In the direction perpendicular to the base substrate, the firstpretreatment region overlaps the light emitting device, and the secondpretreatment region surrounds the first pretreatment region. Forexample, the hydrophobic process is used to pretreat the firstpretreatment region to form a central region, and the secondpretreatment region forms a peripheral region without the pretreating.As another example, the hydrophilic process is used to pretreat thesecond pretreatment region to form a peripheral region, and the firstpretreatment region forms a central region without the pretreating. As afurther example, the hydrophobic process is used to pretreat the firstpretreatment region to form a central region, and the secondpretreatment region is pretreated by the hydrophilic process to form aperipheral region.

In another embodiment, the roughness of the central region is smallerthan the roughness of the peripheral region, so that after the lightadjustment unit precursor is form by the inkjet printing process, it isuneasy for the central region to be wetted by ink droplets, while theperipheral region is more easily wetted by ink droplets than the centralregion. During the evaporation of the solvent in the light adjustmentunit precursor, the ink in the central region is more likely to gathertowards the peripheral region, and after the solvent evaporates, a lightadjustment unit having through holes is formed. After the pretreating, acentral region and a peripheral region that have different roughness areformed, which can play an auxiliary role in the process of manufacturingthe light adjustment unit. In addition, a difference between theroughness of the central region and the peripheral region can beadjusted by adjusting pretreatment process parameters, so as to controlan area of the through hole in the light adjustment unit. In the displaypanel, the plurality of light emitting devices includes a red lightemitting device, a green light emitting device, and a blue lightemitting device. In this way, the through holes overlapping the lightemitting devices of different colors can be formed to have differentareas based on design requirements.

Specifically, step S204 pretreats the surface of the pre-contact layerfacing away from the base substrate to form a contact layer by thefollowing process. A nanocrystalline layer is formed on the pre-contactlayer to form a plurality of central regions and a peripheral region.The larger density of nanoparticles in the nanocrystalline layer leadsto the smaller surface roughness. The surface of the pre-contact layeris divided into a first pretreatment region and a second pretreatmentregion. In the direction perpendicular to the base substrate, the firstpretreatment region overlaps the light emitting device, and the secondpretreatment region surrounds the first pretreatment region. Ananocrystalline layer having a relatively high density is formed in thefirst pretreatment region to form a central region, and ananocrystalline layer having a relatively low density is formed in thesecond pretreatment region to form a peripheral region.

The above are representative embodiments of the present disclosure andare not intended to limit the present disclosure. Any modifications,equivalents, improvements, etc., which are made within the spirit andprinciples of the present disclosure, should be included in the scope ofthe present disclosure.

Finally, it should be noted that, the above-described embodiments arefor illustrating the present disclosure but not intended to provide anylimitation. Although the present disclosure has been described in detailwith reference to the above-described embodiments, it should beunderstood by those skilled in the art that, it is still possible tomodify the technical solutions described in the above embodiments or toequivalently replace some or all of the technical features therein, butthese modifications or replacements do not cause the essence ofcorresponding technical solutions to depart from the scope of thepresent disclosure.

What is claimed is:
 1. A display panel, comprising: a base substrate; alight emitting device layer provided on the base substrate, the lightemitting device layer comprising a light emitting device; and a lightadjustment structure layer provided at a side of the light emittingdevice layer facing away from the base substrate, wherein the lightadjustment structure layer comprises a light adjustment unit, and thelight adjustment unit comprises a through hole overlapping the lightemitting device, wherein the light emitting device comprises a firstlight emitting device and a second light emitting device, a color oflight emitted from the first light emitting device is different from acolor of light emitted from the second light emitting device, and alight emitting area of the first light emitting device is greater than alight emitting area of the second light emitting device, the lightadjustment unit comprises a first light adjustment unit corresponding tothe first light emitting device and a second light adjustment unitcorresponding to the second light emitting device, and a refractiveindex n1 of the first light adjustment unit is less than a refractiveindex n2 of the second light adjustment unit.
 2. The display panelaccording to claim 1, wherein the first light emitting device is a bluelight emitting device, and the second light emitting device is a redlight emitting device, or wherein the first light emitting device is theblue light emitting device, and the second light emitting device is agreen light emitting device, or wherein the first light emitting deviceis the green light emitting device, and the second light emitting deviceis the red light emitting device.
 3. The display panel according toclaim 1, further comprising: a dielectric layer covering the lightadjustment unit, wherein the refractive index n1 of the first lightadjustment unit and the refractive index n2 of the second lightadjustment unit are both less than that of the dielectric layer.
 4. Thedisplay panel according to claim 1, wherein the light adjustment unitfurther comprises a light adjustment sub-section surrounding the throughhole, and along a direction from the through hole to the lightadjustment sub-section, a thickness of the light adjustment sub-sectionprogressively increases.
 5. The display panel according to claim 4,further comprising: a dielectric layer covering the light adjustmentunit, wherein an interface between the dielectric layer and the lightadjustment sub-section is an arc-shaped surface.
 6. The display panelaccording to claim 4, further comprising: a dielectric layer coveringthe light adjustment unit, wherein an interface between the dielectriclayer and the light adjustment sub-section is a convex surfaceprotruding from the light emitting device layer along a direction awayfrom the base substrate.
 7. The display panel according to claim 1,wherein the light adjustment unit comprises a first surface protrudingalong a direction away from the base substrate.
 8. The display panelaccording to claim 1, wherein an orthographic projection of the lightadjustment unit has a ring shape.
 9. The display panel according toclaim 1, wherein the light adjustment unit is in a ring-shaped convexlens structure, and the through hole of the light adjustment unit is ata center of the ring-shaped convex lens structure.
 10. The display panelaccording to claim 1, further comprising an encapsulation layer and atouch film group layer, wherein the encapsulation layer and the touchfilm group layer are both located between the light emitting devicelayer and the light adjustment structure layer, and the encapsulationlayer is located between the touch film group layer and the lightemitting device layer, and comprises at least one organic encapsulationlayer and at least one inorganic encapsulation layer.
 11. The displaypanel according to claim 1, wherein the light adjustment unit comprisesa plurality of light adjustment units spaced apart from each other. 12.The display panel according to claim 1, wherein the light adjustmentunit comprises a plurality of light adjustment units, a light adjustmentunit of the plurality of light adjustment units is in contact with itsadjacent light adjustment unit.
 13. A display device comprising adisplay panel, wherein the display panel comprises: a base substrate; alight emitting device layer provided on the base substrate, the lightemitting device layer comprising a light emitting device; and a lightadjustment structure layer provided at a side of the light emittingdevice layer facing away from the base substrate, wherein the lightadjustment structure layer comprises a light adjustment unit, and thelight adjustment unit comprises a through hole overlapping the lightemitting device, wherein the light emitting device comprise a firstlight emitting device and a second light emitting device, a color oflight emitted from the first light emitting device is different from acolor of light emitted from the second light emitting device, and alight emitting area of the first light emitting device is greater than alight emitting area of the second light emitting device, the lightadjustment unit comprises a first light adjustment unit corresponding tothe first light emitting device and a second light adjustment unitcorresponding to the second light emitting device, and a refractiveindex n1 of the first light adjustment unit is less than a refractiveindex n2 of the second light adjustment unit.